Are you really getting what you pay for when you fill up your gas tank?

Gas prices shot up 30 cents at some stations Wednesday, to $3.99 for a gallon of regular unleaded. 13 Investigates is making sure you're getting what you pay for at the pump.

Sometimes, you just don't have a choice when your gas tank is on empty, and you have to stop at the first gas station possible. Which happened to Scott Ballentine when Eyewitness News found him filling up his gas tank.

"Do you see where this pump has been inspected?" we asked.

"Uh, no," Ballentine replied.

So how does he know he is getting what he paid for?

"I guess I'm just a trusting individual," he said.

That makes Ballentine a dream customer, he is trusting that the money he is spending, he believes, will equal the right amount of gas in the tank.

An Eyewitness News investigation revealed that thousands of pumps in central Indiana had not been inspected every year as the law requires. Investigative Reporter Bob Segall found gas pumps in a various forms of neglect and city inspection stickers too small or faint to read.

In response to our investigation, The City of Indianapolis added four inspectors and claim to have inspected or re-inspected 85 percent of the 9,000 gas pumps, with plans to finish all inspections by the July 4th weekend.

After the inspection is done, an easier to read, larger, brighter sticker is put on the pump. On the sticker is a new hotline for complaints from drivers.

Since the beginning of the year, dozens more people have called the number. Some of those complaints have led to pumps being shut down.

At any one time, according to the City of Indianapolis, 10 percent of the pumps are not operating properly.